Sound Characteristics:The C-2SA applies diamond differential amp. It has its particular
musical sound flavors which can't be found in any other amp design.
Its sound a bit of softness, warm and relaxed, allows users to
pleasantly listening for a long time. Its sound is on the musical
side but the detail and dynamics are still reproduced.

The C-2 SA functions:Front
plate:Volume knob: Control the volume
level of the headphone/pre amp. Gain
button: Push in for high gain (+13DB), out for low gain (+4DB). Pre button: Push in for
preamp output, out for
headphone output.Selector
knob: Select input signal.

Design Features:

Sources
selector:The C-2SA input selector allows
users to set the shorting functions. It can be set to short out the
unused input signal to GND just to avoid the disconnected input signal
from affecting the active input signal. To enable this setting, users
just push the jumpers on, see the below photo. But if users use one
source to feed to two amps, there may be no sound while the C-2SA is
powered off, so users can pull off the jumpers in this case.

Click image to enlarge.

Diamond Differential
amp: Benefits from the high speed diamond differential amp circuits,
excellent linearity and low phase distortion, diamond differential
circuit is being loved and supported by more and more audio fans.
Although the circuit is complex, the sound quality is impressive.
We've done a lot of study and experiments on diamond differential
current these many years, aiming to get a better solution of circuit
design.

The diamond differential amp circuits is a non-global feedback
technology made with fully discrete amplifiers. Most people know the
global
feedback design can offer better specs in test measurements, and
non-global feedback can't do well in test measurements but can offer
better sound to human ears. Here is a conflict of the classic circuits.
But
in C-2SA, we applied an accelerator before the output stages which can
reproduce perfect test performance based on a non-feedback output stage.
The input buffers are
Non-feedback. It can keep all input signal at low impedance to reach
the best performance of the diamond differential amp.
The volume applies parallel
connection mode which can offer better sound than the standard mode.

Click image to enlarge.
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The power supply
is more important for sound reproduce, in C-2SA applied the high
speed Discrete PSU +/- 33VDC power supply for the Diamond Difference
amps. They can offer pure and quick power supply for driving
the headphone exactly. The high voltage power supply can drive most
headphone from 15 to 600 ohms as well.Click image to enlarge.

C-2SA is
a fully discrete amp without any OPA inside, It is also without couple caps and DC servos,
has a non-feedback output stage, and must depend on how exactly-matched
transistors are. This is hard work which most factories are unwilling
to do. But this configuration is the way to arrive at better sound.

Hi-end grade construction:

The
C-2SA
uses a 80W high performance transformer. The NOVER capacitors are
specially custom ordered from
NOVER (U.K.) according to Audio GD's requirement. To achieve Silent
operation, the control
circuit is powered with separate regulator.

The C-2SA
uses high grade DALE resistors.
RCA sockets are custom
ordered and 24k gold-plated. All transistors are exact-matched Toshiba
and Hitachi.

The C-2SA applies
the custom order ALPS 27 volume pot to reduce channel imbalance and
improve sound quality, the quality is higher and much more costly
than the standard ALPS 27 more common in the market.

All-aluminum
chassis
can reduce noise pick up.

The
PCB
employs
2MM
double
copper/stringy board, 70uM copper.

All
Audio-gd's
workers
are
hi-fi
enthusiasts and skilled electronic
assemblers.

Prior
to
shipment,
our
products
are burned-in for 100 hours, and
undergo at least 10 times a variety of tests to ensure they work
perfectly for the customer.

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C-2 SA SpecificationImprovement may result in changes in
specifications and
design without notice.